Furnace



Jan 11 1927' F. A. LIPPERT FURNACE Filed June 9. 1924 Patented Jan. 11, 1927.

PATENT OFFICE.-

FREDERICK A. LIPPERT, CHICAGO, ILLINOIS.

FURNACE.

Application filed June 9,

This invention relates to furnaces particularly suitable for heating air and suitably arranged for combustion of gaseous or liquld fuel.

The objects of the invention are to provide an improved method and means suitable for transferring heat from products of combustion to a heat receiving medium, such as air, within a very limited space, considering the rate at which the heat is developed and transferred.

The objects of the invent-ion may be ac complished by the use of apparatus, asl shown in the drawing, which is a longitudinal, vertical section of a combustion cham-A ber and conduit or chamber for the products of combustion surrounded by a conduit in which the heated medium flows oppositely to the direction l'of flow of the products of combustion.

The construction by which the invention may be put into practice comprises an insu- 4 lated combustion chamber which is designed to increase the capacity from end to end thereof in proportion to the expansion of the burning gases, and a heat transferring compartment communicating with the combustion chamber having walls of good conductivity and of conical form so that the carrying capacity of Ithe heat transferring compartment substantially` decreases aocording to the contraction of the products of combustion upon cooling and also for the purpose of fairly uniformly'maintaining the rate of heat transference at different points along the wall of the heat transferring compartment. A Asimilarly tapered Iiacket surrounds and is spaced from the heat transferring compartment and air or other heated medium is caused to travel through this space oppositely to the products of combustion providing increasing space for such air as it expands according to the rise in temperature.

The combustion chamber 1 is shown as enlarging in area from the inlet end 2 to the discharge end 3. This combustion chamber issuitably lined with a refractory material 4, which, as usual, assists in the process of combustion by properly insulating the Hame from the outer metallic wall 5 of the combustion chamber. TheA products of combustion, in leaving the combustion chamber 1924:Y Serial No. 718,780.

1, enter a frusto-conical heat transferring compartment 6 form-ed by uninsulated metallic wall 7. This compartment communicates fat its opposite end with anV outlet ilue 8. Surrounding the outlet flue .8 is a drumV 9 communicating with a blower 10 and having a discharge opening 11 communicating with a space 12 surrounding the wall `7,and formed by this wall, and an outer jacket 13 spaced therefrom. At its lower end the jacket 13 is provided with openings 14 for the discharge of air passing from the blower through the space 12.

With this arrangement, the capacity of the combustion chamber 1 increases substantially as the expansion of the burning gases, while the capacity of the heat transferring compartment 6 decreases from its inlet end to its opposite end substantially as the products of combustion contract upon delivery of heat through the wall.7. The carrying capacity of the space 12 likewise varies from end to end of the wall 13 to be substantially proportional to the expansion of the heated air or other medium pumped through the space 12 oppositely to the direction of travel of the products of combustion.

In order to very greatly lengthen the path of travel of both the products of combustion and the heated medium, within the dimensions of a device of this shape, direct travel of the gases from end to end of the furnace is prevented by means of .a helical rib 18 within-the combustion chamber, and extending from side to side thereof throughout its length. The space for the heated medium surrounding the combustion chamber is likewise divided by a helical deflector 19 extending from end to end thereof.

In operation ofthe furnace,4 the burning fuel travels in the direction indicated by arrow 15. Products of combustion traveling from the combustion chamber 1 n a.

helix of gradually decreasing radius and outwardly as indicated by arrow 16. The air to be heated is pumped through compartment 12 in the direction indicated by' tion according to the loss of heat by the 'I latter.

Although but one specific. embodiment of this invention has been herein shown and described, it is to be understood thatnumer'- ous details of the construction shown may be altered or omitted without departing from the spirit of this invention as defined by the following claims: r

I claim:

1. The method of transferring heat from products of combustion to another medium, which consists in causing the products of combustion to travel in a helix of gradually decreasing radius and causing the heated medium to travel in an opposite path around the products of combustion in a helix of gradually increasing radius.

'2. A furnace ofthe class described, comprising a wall structure forminga combustion chamber of gradually increasing dimensions from its inlet to its outlet end, anita heat transferring compartment communica ing with the outlet end of said combustion chamber and formed to gradually decrease in carrying capacity from the discharge end of said combustion chamberto the discharge end of said heat transferring chamber.

3. A furnace of the class described, comprising a wall structure forming a combustion chamber of gradually increasing dimensions from its inlet to its outlet end, and a heat transferring compartment communicating with the outlet end of said combustion chamber and formed to gradually decrease v in carrying capacity from the discharge end of said combustion chamber to the discharge end of said heat ltransferring chamber, said heat transferring chamber being provided with a helical deflector extending substantially from end to end thereof and adapted to increase the normal contact ofthe products of combustion with the wall of said heat transferring compartment.

f tion chamber of gradually increasing dimen 4. A furnace of the class described, comprlsing a wall structure forming a combusf sions Vfrom its inlet to its outlet end, a heat transferring compartment communicating with' the Aoutlet end of said combustion chamber and formed to gradually .decrease in carrying capacity from the discharge end of said combustion vchamber to `the discharge end of said heat transferring chamber, and a jacket spaced from and surround-l ing said heat transferring compartment.l said jacket cooperating with the Wall of said,

heat transferring compartment to form a' conduit varying in carrying capacity in accordance with the varying carrying capacity 'of said heat transferring compartment..

5. A furnace of the class described, coml *prising a wall structure forming a combustion chamber f gradually increasing dimensions from its inlet to its outlet end, a heat with the outlet en transferring com artment communicating of said combustionjchamber and formed to gradually decrease 1n car-l rying'capacity from' the discharge end ofl said combustion chamber to the discharge end of saidheat transferring chamber, and a jacket spaced from and surrounding said heat transferring compartment, said jacket-- tion chamber. of gradually increasing'dimenlsions from its inlet to its outlet end, a heat transferring compartment communicating with the outlet end of said combustion chamberand formed togradially ldecrease in carrying capacity `from the discharge end of said combustion chamber tol the-discharge end of said heat transferring chamber, and a jacket spaced from and surrounding said heat transferring compartment, said jacket cooperating with the wall of said heat transferring compartment to form a conduit varying in carrying capacity, in accordance with the varying carrying capacity o f said heat transferring compartment, and a helical deflector extending Yalong vthe passage- Way between said jacket andsaid heat transferring compartment. A

7. A furnace of the class described, comprising a wall structure forming a combustion chamber and a heat transferring compartment, said heat transferring compartment being tapered from the combustion chamber toward its opposite end, a jacket surrounding said heat transferring compartment and tapered to correspond therewith, a deilecting helix on the interior surface of `said heat transferring compartment and a deflecting helix on the exterlor surface of said heat transferring compartment in the space between said compartment and they surrounding jacket.

8. A furnace of the class described, comprising a wall structure forming a combustion chamber and a heat transferring compartment, said heat transferring compartment being tapered from the combustion chamber toward its opposite end, a jacket surrounding said heat transferring compartment and tapered to correspond therewith, a deflecting helix on the interior surface of said heat-transferring compartment, and a deflecting helix on the exterior surface of said heat transferring compartment in the space between said compartment and the surrounding jacket, and means for pumping air from end to end of the space one Huid to another by causing oppositel formed by said heat transferring compartdirected currents of the two fluids, at di ment and the surrounding jacket in a direcferent temperatures, through adjacent spi- 10 tion opposite to the normal direction of flow ral or helical paths. 5 of the products of combustion Within said Signed at Chicago this 5th day of June transferring compartment. 1924:.

9. The method of transferring heat from' FREDERICK A. LIPPERT. 

